This proposal is to request support for a Keystone Symposia meeting entitled "Tuberculosis: Biology, Pathology and Therapy", organized by JoAnne L. Flynn, David G. Russell and Thomas N.A. Dick, which will be held in Keystone, Colorado from January 25 - 30, 2009. Tuberculosis kills 2 million people per year worldwide. Although great strides have been made in the past decade in understanding Mycobacterium tuberculosis, the complexity of the disease necessitates a multi-pronged approach. Translating insights related to host-pathogen interplay and bacterial physiology into treatments is complex, requiring academics and industrial scientists to come together in new and creative ways. In humans the infection is persistent and chronic, yet reactivates into fulminating progressive disease. This, and the shortage of appropriate animal models, form major obstacles to identifying factors that determine disease progression and the extensive pathology associated with transmission. This meeting will focus on basic mechanisms of pathogenesis of Mycobacterium tuberculosis, and how the balance of control of infection within the granuloma is influenced by host and bacterial factors. We will also focus on translating basic mechanistic findings to the development of therapies, and a workshop highlighting academic-industrial partnerships is planned. Tuberculosis (TB) remains a worldwide scourge, with 9 million new cases and 2 million deaths per year. Drug resistant strains of TB are prevalent, and new drugs have not been developed for decades, in part due to a lack of new targets. The huge reservoir of persons with latent infection (estimated to be 2 billion people) presents enormous challenges for preventing future transmission and eventually eliminating the disease entirely.